Copolymers of tetrahydroabietyl alcohol-modified unsaturated alkyd resins and vinyl compounds



Patented Get. 18, 1949 COPOLYMERS OF TETRAHYDROABIETYL A L C O H O LMODIFIED UNSATURATED ALKYD RESIN S AND VINYL COMPOUNDS Edward L. Krona,Old Greenwich, Conn., asslgnor as American Cyanamid Company, New York,N. Y., a corporation of Maine Serial No. 653,959

No Drawing. Application March 12,1946,

7 Claims. (Cl. 260-26) This invention relates to polymerizablecompositions, to the polymerization of such compositions to forminsoluble resins, and to the production of coating compositions, moldingcompositions, molded articles, laminated articles, etc., from thepolymerizable compositions. Polymerizable compositions of this inventioninclude a reactive alkyd resin and an organic substance, generally areactive solvent. Upon reaction of these substances, a substantiallyinsoluble. resin is formed.

One of the objects of this invention is to prepare improved resins andespecially to obtain clear and colorless gels.

It is also an object of this invention to provide potentially,polymerizable solutions which would be stable during storage.

Still another object of this invention is to control the rate ofpolymerization of the reactive mixture, as well as to improve theproperties and characteristics of resulting gels.

Another object of this invention is to prepare compounds particularlysuitable for use as coating compositions and as components in coatingcompositions.

A further object of the present invention is to prepare moldingcompositions and especially to prepare clear and colorless moldedmaterials. Another object of this invention is to prepare laminatedmoldings having high strength and other desirable properties.

A still further object of this invention is to provide moldingcompositions suitable for injection molding. Other objects will beapparent from the description.

According to the present invention I have found that substantiallyinsoluble, substantially infusible resins may be prepared by means ofthe chemical reaction or polymerization of a mixture containing a resinpossessing a plurality of polymerizably reactive alpha, beta enalgroups, i. e.

and an organic substance which contains the polymerizably reactive groupCH2=C which has a boiling point of at least 60 C., and which has noconjugated carbon-to-carbon double bonds. Such mixtures may be utilizedin coating compositions, in molding compositions, in laminating, inadhesives, in casting compositions, etc.

For the sake of brevity, the organic substances which contain thepolymerizably reactive group, CH2=C will be referred to herein asreactive materials or as reactive materials containing the CH2=C group,and the" are thus to be distinguished from the resins which possess aplurality of polymerizably reactive alpha, beta enal groups which aredesignated herein as "reactiveresins or as unsaturated alkyd resins.

Many of the reactive materials containing the CH2=C group are solvents,and therefore the reactive resins may be dissolved therein to formliquid compositions which may be used as such without the addition ofany other solvent unless particularly desirable. It is to be understood,however, that I am not restricted to liquid substances which actuallyact as solvents, since in some cases the organic liquid substances mayin fact act as a solute rather than as a solvent, it being dissolved bythe resin, or a colloidal solution may be produced instead of a truesolution. Furthermore, the'reactive material may be a resin containing aplurality of CH2=C groups or CH2=CHCH2 groups. Such a substance could becured by a reactive resin or by a-reactive sub-- stance which containspolymerizably reactive alpha, beta enal groups. Such substances may bederived from alpha, beta unsaturated organic acids, for example, byesterification of such acids.

Among the reactive resins used in the practice of this invention forinteraction with the reactive material containing the CH2=C group arethose which are derived from alpha, beta unsaturated organic acids and,therefore, contain the reactive groupings present in these acids. Theterm acids as used hereinis intended to include the anhydrides as wellas the acids themselves since the former may be used instead of theacid. The term alpha, beta unsaturated organic acid as used in the artdoes not include acids wherein the unsaturated group is part of anaromatic-acting radical, as for example, phthalic acid, and the samedefinition is adopted herein.

Resins used in the practice of the present invention are preferablyproduced by the esterification of an alpha, beta unsaturatedpolycarboxylic acid with a polyhydric alcohol, particularly a glycol, inthe presence of tetrahydroabietyl alco- 1101. Although esterification ofthe acid with a polyhydric alcohol is perhaps one of the simplest,

most convenient ways of obtaining a reactive resin, I am not precludedfrom using resins otherwise derived from alpha, beta unsaturated organicacids. Reactive resins suitablefor my invention are any of thosecontaining a plurality of polymerizably reactive alpha, beta enalgroups.

A reactive resin such as those prepared by esterification of alpha, betaunsaturated organic acids and a glycol or other polyhydric alcohol inthe presence of tetrahydroabietyl alcohol is mixed with th reactivematerial containing the groups, CH2==C:, Upon adding a polymerizationcatalyst and subjecting the mixture to polymerization condition.such'as, for example, heat, light, or a combination of both, asubstantially insoluble, substantialiy infusible resin is obtained.

All of the reactive substances suitable for use according to myinvention for reaction with a reactive resin are characterized by thepresence of the reactive group CH2=C and none or them containsconjugated aliphatic carbon-to-carbon double bonds. Compounds containinga conjugated system of aliphatic carbon-to-carbon double bonds are knownto react with themselves or with other unsaturated compounds such as themaleic esters, by a 1,2 or 1,4 addition mechanism such as that which hasbecome generally known as theDiels-Alder reaction. On the other hand,compounds such as those used according to the present invention whichcontain no conjugated aliphatic carbon-to-carbon double bonds obviouslycannot undergo this type of reaction with the maleic esters.Accordingly, my inventionis not directed,to the use of unsaturatedcompounds containing conjugated systems of aliphatic caro-, m-,p-isopropenyl toluenes, the 2,3-, 3,4-, 2,4-,

2,5- and 2,6-dimethyl styrenes, isopropenyl benzene, styrenes containingone or more nuclear substituted fluorine or bromine groups, vinylnaphthalene, vinyl mesitylene, 0-, m-, p-vinyl dipolymerizing any of thefollowing with a polymerizably reactive resin of the type describedabove, 1. e., unsaturated alkyd resins containins a plurality of alpha,beta enal groups: 'allyl alcohol, methallyl alcohol, allyl acetate,allyl lactate,

the allyl ester of alpha-hydroxyisobutyric acid,

allyl acrylate, allyl methacrylate, diallyl carbonate, diallyl malonate,diallyl oxalate, diallyl succinate, diallyl gluconate, diallylmethylgluconate.

diallyl adipate, the diallyl ester of azelaic acid,

diallyl sebacate, diallyl tartronate, diallyl tartrate, diallylsilicone, diallyl silicate, diallyl iumarate, diallyl-maleate, diallylmesaconate, diallyl citraconate, diallyl glutaconate, the diallyl esterof muconic acid, diallyl itaconate, diallyl phthalate, diallylchlorophthalate, the diallyl ester of endomethylene tetrahydrophthalicanhydride, triallyl tricarballylate, triallyl aconitate, triallylcitrate, triallyl phosphate, trimethallyl phosphate, triallyl silicone,triallyl cyanurate, tetraallyl silicate and other tetraallyl esters.Other allyl esters including those disclosed in my copending applicationSerial No. 555,194 filed September 21, 1944, now

'U. S. Patent 2,443,741, may be substituted for any of the above-listedcompounds.

The polymerization catalysts include the organic superoxides, aldehydicand acidic peroxides. Among the preferred catalysts there are: theacidic peroxides, e. g. benzoyl peroxide, phthalic peroxide, succinicperoxide and benzoyl acetic peroxide; fatty oil acid peroxides, e. g.coconut oil acid peroxides, lauric peroxide, stearic peroxide and oleicperoxide; alcohol peroxides, e. g. tertiary butyl hydroperoxide usuallycalled tertiary butyl peroxide and terpene oxides, e. g. ascaridole.Still other polymerization catalysts might be used in some instancessuch as soluble cobaltsalts (particularly the linoleate andnaphthenate),

phenyls, vinyl carbazole, vinyl phenols, vinyl furane; dialkyl esters ofmaleic acid, fumaric acid and itaconic acid (including dimethyliumarate, dimethyl maleate, diethyl maleate, dibutyl fumarate, dimethylitaconate, dibutyl itaconate). etc.

Allyl compounds, 1. e., those containing the CH2=CH--CH2 group may alsobe used. Of the allyl compounds esters form a large class all of whichare suitable. The reactive allyl compounds which have been which may beused, the allyl I found to be most suitable are those having a highboiling point such as the diallyl esters, e. g. diallyl maleate, diallyli'umarate, diallyl phthalate and diallyl succinate. Other allylcompounds may also be used which are not necessarily high boiling. Aspointed out in my copending applicatio Serial No. 487,034, filed May 14,1943, now abandoned, substantially insoluble and substantially infusibleresins may be prepared by reacting orp-toluene sulfonic acid, aluminumchloride,'stannic chloride and boron trifluoride.

The term polymerization catalyst as used in this specification is notintended to cover oxygen contained in the resin as an impurity. Whilethis small amount of oxygen would only catalyze the reaction to a verysmall extent, in order to eliminate any ambiguity the termpolymerization catalyst is specifically defined as excluding any oxygenpresent as an impurity in the resin itself.

The concentration of catalyst employed is usually small, 1. e., for thepreferred catalysts from about 1 part catalyst per thousand parts ofthe' reactive mixture to about 2 parts per hundred parts of the reactivemixture. If an inhibitor be present, up to 5% or even more of catalystmay be necessary according to the concentration of inhibitor. Wherefillers are-used which contain high concentrations of substances whichact as inhibitors. e. g. wood flour, the concentration of catalystnecessary to effect polymerization may be well above 5%.

The polymerization conditions referred to are heat, light, or acombination of both. Ultraviolet light is more effective than ordinarylight.

The temperature of conversion depends somewhat on the boiling point ofthe reactive material and' also on the pressures used. At atmosphericpressure, as in coating and casting operations, temperatures near orabove the boiling point are unsuitable in most instances sincesubstantial amounts of the reactive material would be lost byevaporation before the reaction between the resin' and reactive materialcan be completed. Accordingly, a temperature between room temperature(about 20-25 C.) and the boiling point is usually-employed wherepolymerization of this tion doubles for about nature is carried out. Therate of polymerizaeach ten degrees (0.) rise in temperature for thisreaction. A temperature is selected which will give a suitable reactionrate and yet not cause substantial volatilization. The

,following table shows the approximate polymerization temperatures mostsuitable for the named reactive materials:

, Preferred- Reactive Material Temperature Range Temperature e o.diallyl maleate room temp. to about 110 C 50 to 90 diallyl phthalateroom temp. to about 150 C. 50 to 90 Obviously it.will be necessary touse lower temperatures if large or very thick pieces are being castbecause of the exothermic reaction and poor heat conductivity of thereacting mixture.

Where suitable precautions are taken to prevent evaporation'of myreactive material or where pressure molding is used, higher temperaturesthan those mentioned above can be used. Since the time of curing isdesirably much shorter (in pressure molding at elevated temperatures)and since the reactive material containing the group would not be lostso easily, a higher temperature is preferred.

The particular reactive resin, reactive material and catalyst isselected according to the type of product desired, taking into accountthe'solubilities of the reactants as the resulting gels. Somecombinations of reactive resins and reactive materials result in opaquegels while others give clear products in the gel state. Obviously formany purposes the opaque gel may Example 1 A resin obtained by thereaction of fumaric acid,

diethylene glycol and tetrahydroabietyl alcohol (resin A) is cut withdiallyl phthalate to form a solution composed of 2 parts of resin to 1part of. diallyl phthalate. To 100 parts of said solution 0.005 part ofbenzoyl peroxide, 0.0003 part of cobalt naphthenate and 0.0004 part ofmanganese naphthenate are added. The resulting composition is applied toa rather coarse weave of glass cloth. The impregnated cloth is cut andstacked to form an assembly which is cured by heating in air for about 2hours at 100 C. The surface is tack-free, and during the heatingtheresin pulls itself down between the fibers on the surface leaving arough uniform exterior which could be used as an excellent base for oilpainting since the rough surface readily pulls paint from a brush. Usinga fabric of a linen weave, the surface of th laminate could be madesmooth.

Example 2 A resin prepared by reaction of diethylene glycol, fumaricacid, tetrahydroabietyl alcohol and linseed oil fatty acids (resin B) iscut with diallyl phthalate in a ratio of 3 parts of resin to 2 parts ofdiallyl phthalate thereby producing a well as the character of about GH(Gardner-Holt).

solution having a viscosity Holt). A solution containing equal parts ofthe resin and diallyl phthalate has a viscosity of To parts of either ofthese solutions the following is' added:

Part Cobalt naphthenate 0.004 Manganese naphthenate 0.002 Benzoylperoxide 0.15

Films of the resulting solution about 1 hour at around coatings.

dry tack-free in C. to yield hard Ewample 3 solution are added 0.01 partof hydroquinone and Films of the resulting solution dry tack-free inabout 1 hour at 125 C. to yield a hard coating.

Example 4 Parts Fumaric acid 638 Ethylene glycol 310 Tetrahydroabietylalcohol 292 All of the materials are mixed together and heated under anatmosphere of carbon dioxide to to about C. for 6 hours and C. for 8hours, to obtain a resin having an acid number of 49. The resin is clearand viscous while hot, but upon cooling and standing it hardens andslowly becomes opaque due to crystallization.

Example 5 Parts F'umaric acid 638 1,3-butylene glycol 450Tetrahydroabietyl alcohol 292 The materials are mixed together andheated at about 200 C. for 8 hours under an atmosphere of carbondioxide. The clear very stiff resin The materials are mixed together andheated at 180 C. for about 3 hours under an atmosphere of carbondioxide. The clear dark colored resin is of a heavy syrupy consistencyand has an acid number of 48.

The resins of Examples 4, 5 and 6 may be cut with diallyl phthalate orst'yrene as in Examples 1, 2 and 3.

In place of part or all of the diallyl phthalate employed in Example 1and 2 or of the styrene employed in Example 3, I may substitute any ofthe other reactive compounds containing the CH2=C group previouslymentioned herein. Moreover I may substitute equivalent, molarproportions of these reactive compounds or I may vary the'proportionsthereof. Any desired proportion of reactive compound to unsaturatedalkyd resin may be used, but I prefer to use from 5%-95% of oneingredient with corresponding amounts of 95%5% of the other. If thecopolymer product is intended for use in laminating or molding, then Iprefer a weight ratio of ingredients of from 4:1 to 1:4.

Part. of the tetrahydroabietyl alcohol modified of 'M-N (Gardener- 8%cobalt naphthenate solution.

unsaturated alkyd resin may be replaced by an unmodified unsaturatedalkyd resin or by unzsaturated alkyd resins modified with other alcoholsor acids.

Viscosity adjustmentoj reactive mixture an esteriflcation catalyst, e.g. p-toluene'sulfonic enemas acid, andthen heating until the viscositygoes "down. The mechanism of this change is probably re-esterification.This is also useful when the composition is to be baked at hightemperature, under which conditions the reactive material would be lostin part byevaporation. If this thinning process is carried out, thereactive material is combined with the resin by re-esteriflcation and isnot lost. It is also desirable to add a polymerization inhibitor beforethe heating or thinning process.

I In casting or molding operations using a mixture of a reactive resinand reactive material containing the CH2=C group, it may sometimes bedesirable to body the reactive mixture before adding the catalyst inorder to cut down the induction period which would otherwise be toolong. This may be done by heating a mixture of resin and reactivematerial from about 70 C. to about 110 C., preferably at about 90 C.,for a suflicient length of time to substantially reduce the inductionperiod. This time will vary with each resin-reactive materialcombination with the initial viscosity and other such factors but may bedetermined by observation of the rise of viscosity/ The heating shouldcontinue until ,the viscosity begins to rise rapidly. A gen-- eral rulefor determining the heating time is to heat the mixture until theyiscosity is about two tothree times the initial viscosity.

After the bodying operation is carried out, the polymerization catalystis added to the mixture and the whole subjected to polymerizationconditions. The use of liquid peroxides instead of solid peroxides is anadvantage after bodying the resin mixture since it is. difficult to getthe solid peroxides dissolved rapidly enough. Peroxides'of the coconutoil acids, tertiary butyl peroxide and ascaridoleare suitable liquids.

By the use of-this rocess the induction period Addition 0]" inhibitorsOne of the difiiculties in the use of the compositions described aboveis that they are not,

susceptible to storage in the mixed form because polymerization willusually take place even at room temperature within a comparatively shorttime. Moreover, when it is desired to cure the compositions very rapidlyunder heat and pressure, the reaction becomes at times so vigorous thatit cannot be controlled. In order to overcome these difliculties it hasbeen found advisable to incorporate a small proportion of apolymerization inhibitor in the mixture of resin and reactive material.When it is desired to usethis mixture, a small percentage of thepolymerization catalyst is added sufficient toovercome the effect of theinhibitor as well as to promote the polymerization. By careful controlof the concentrations of inhibitor and catalyst, a uniform product witha good reaction velocity is obtainable. Upon subjection of this mixtureto polymerization conditions such as heat, light or a combination ofboth, with or without pressure, an infusible, insoluble resin isproduced which has many more desirable characteristics than the resinsproduced by the polymerization of mixtures not containing thepolymerization inhibitor such as, for 'mstance, the lack of fracture.

Suitable polymerization inhibitors for this reaction are phenoliccompounds, especially the polyhydric phenols, and aromatic amines. Spe

cific examples of this group of inhibitors are hydroquinone,benzaldehyde, ascorbic acid, isoascorbic acid, resorcinol, tannin, sym.di-beta naphthyl-p-phenylene diamine, and phenolic resins.

' Sulfur compounds are also suitable.

The concentration of inhibitor is preferably low, and I have found thatless than about 1% is usually sufficient. However, with the preferredinhibitors, I prefer to use only about 0.01% to about 0.1%.

The inhibitor may be incorporated in the reactive resin-reactivematerial combination (either before or after bodying) or it may be addedto the original reactive resinbefore or during the esteriflcation of thesaid reactive resin. By add- .ing the inhibitor before the'esterification it is is cut down from approximately /2 to A; the timethat is required when the bodying-process is not used. Even greaterreductions are obtained with some mixtures.

In bodying reactive mixtures containing the reaction resin and'areactive material containing the CH2=C group wherein the proportions ofreactive material are greater than about 30%, the viscosity rise is sosudden that it may be somewhat difflcult to control. Accordingly, if itis desired to body a resin-reactive material mixture containing morethan 30% of reactive material, an alternative procedure is used. By thismethod one first bodies a mixture containing only 30% of reactivematerial; Then a small portion of additional reactive material is added,for' example, sufficient to make the reactive material concentration40%, and then this is bodied. If still more reactive material isdesired, another small portion of reactive material is added and thebodying process repeated. This process is repeated until the desiredconcentration and viscosity is obtained.

sometimes possible to use an inhibitor which would otherwise besubstantially insoluble in the reactive resin reactive materialcomposition. By adding the inhibitor to the unesterified mixture theinhibitor may become bound into the resin upon subsequentesterification.

Reactive resins and their preparation Reactive resins suitable for.polymerization with reactive materials containing the CH2=C group inaccordance with the teachings of my invention are ,those which contain aplurality of alpha, beta enal groups. The simplest members of'this groupare those produced by the esteriflcation of an alpha, beta-unsaturatedorganic acid with a polyhydric alcohol.

The preferred polyhydric alcohols are those which contain only primaryhydroxyl groups since the presence of secondary hydroxyl groups may makeit diflicult to obtain rapid esteriflcation. The glycols, are generallypreferable. If colorless resins be desired or if optimum electricalproperties be desired, it is preferable to use glycols which'do not haveany oxygen bridges in their structure since the presence of oxygenlinkages may lead to the. formation of color bodies during thepreparation of the resin. By the use eneral.

of glycols which do not contain the oxygen bridges, clear colorlessresins may be produced. On. the other hand, oxygen bridges may bedesirable if the resin is-to be used in coating as they cause films todry faster.

The particular choice of glycol or other polyhydric alcohol used inpreparing the resin is governed mainly by the desired physicalproperties of the intermediate and final polymerization products,especially hardness, impact resistance, distensibility, refractiveindex, adhesion, compatibility relationships, etc., including alsosolvent, water, alkali, acid or chemical resistance in The alpha, betaunsaturated organic acids which I prefer to use in preparing thereactive resins include maleic, fumaric, itaconic and citraconic,although other similar acids could be substituted such as mesaconicacid, aconitic acid and halogenated maleic acids, such as chlormaleicacid, and any of the foregoing could be substituted in part by acrylic,beta benzoyl acrylic,

methacrylic, A -cyclohexene carboxylic cinnamlo, and crotonic acids.Obviously, various mixtures of these acids can be used where expedient.

The reactive resins may be modified with other substances which are usedin alkyd resins, i. e. monohydric alcohols, monobasic acids, or dibasicacids, e. g. Phthallc acid, succinic acid, glutaric acid, adipic acid,azelaic acid, sebacic acid, etc.,

. which do not contain groups polymerizably reactive with respect toorganic substances containing Cm=C groups. Those reactive resins of thepresent invention are modified with tetrahy droabietyl alcoholspecifically. The modifying agents are usually used as diluents orplasticizers, chemically combined in the resin. The use of a smallproportion of the saturated dibasic acids 7 generally improves themechanical properties of the resins after copolymerization with thematerial containing the CH2=C group.

The reactive resins may be prepared from polyhydric alcohols other thanthe glycols or from mixtures including a glycol and a higher polyhydricalcohol. Examples of these are glycerol, pentaerythritol, etc.Polyhydric alcohols containing more than two hydroxyl groups react veryreadily with the alpha, beta unsaturated organic acids.

Consequently, it may be preferable to use some monohydric alcoholin-conjunctlon with the alcohols which contain more than twohydroxylgroups or else some monobasic acid may be used.

It is also possible to introduce initially into the resin structure acertain number of groupings of the type CH2=C through the use ofunsaturated alkyl compounds. One way of accomplishing this, for example,is by direct esterification of an unsaturated alcohol containing a CH2=Cgroup. Examples of such alcohols are allyl alcohol and methallylalcohol.

While the reactive resins may be modified in the same general manner asother alkyd resins, it is preferable to have at least 20% polyhydricalcohol in the reactive mixture and at least 25% polybasic acid in saidreactive, mixture. If a monohydric alcohol or a dibasic acid which doesnot contain polymerizably active groups with respect to organicsubstances containing the CH2=C groups be used, the proportion of suchsubstance will depend on the properties required of the polymerizedreactive material-reactive resin mixture. By the use of a relativelylarge proportion of a polymerizably active dibasic acid, e. g; maleic,in the reactive resin, a hard, tough polymer is produced upon subsequentreaction oi said reactive resin with a reactive material containing theCH2=C group. On the other hand, if the reactive resin is obtained from arelatively smallproportion of polymerizably active dibasic acid and arelatively large proportion of acids which do not contain groupspolymerizably active with respect to organic substances containing CH1=C groups, a softer and more rubbery resin results upon polymerizationwith a reactive material containing the CH2=C group. The same eflect isproduced by the introduction of other inactive ingredients. By varyingtheingredients and the proportions of the ingredients, resins may beobtained having properties desirable for almost any particularuse.

The unsaturated alkyd resins employed in accordance with my inventionare preferably those having an acid number not greater than 50, althoughin some cases resins having an acid number as high as 100 may bedesirable. Generally the acid number should be as low as possible, butthis is sometimes controlled by practi cal considerations of operationsuch as time, temperature and economy.

The resins should be so formulated that the carboxyl groups of the acidsare reacted with the theoretical molar equivalent of the hydroxyl groupsof the alcohols. In this connection it is to be noted that the hydroxylgroups of modifying alcohols as well as the carboxyl groups of modifyingacids should be included with the hydroxyl groups and carboxyl groups ofthe'principal reactants, the polyhydric alcohol and the alpha, betaunsaturated polycarboxylic acid, respectively.

When glycols are reacted with dicarboxylic acids it is preferable thatthe glycol be present in a molar ratio to the acid of not less than 1:2and that the molar ratio of monohydric alcohol to dicarboxylic acid benot greater than 1:1. In most cases it has been found that a molar ratioof monohydric alcohol to dicarboxylic acid of 1:6 produces the bestresults (5.5 mols of glycol being employed in this case). The samegeneral rules apply when polyhydric alcohols other than glycols such aspentaerythritol, dipentaerythritol or polyallyl alcohols are used, orwhen other polycarboxylic acids having more than two carboxylic groupsare used. In other words, the ratio of the monohydric alcohol to thepolycarboxylic acid should preferably be not greater than 1:1 althoughhigher ratios of monohydric alcohol may be employed if desired. However,for optimum results the ratio of monohydric alcohol'to polycarboxylicacid should not exceed 1 mol of monohydric alcohol for each carboxylgroup of the polycarboxylic acid in excessof 1. Thus, for example, aresin may be prepared by the reaction of 1 mol of dipentaerythritol with5 mols of fumaric acid and 4 mols of monohydric alcohol. If it bedesirable to introduce lower alkyl groups into the resin, this may bedone by using maleic esters of monohydric alcohols, e. g. ethyl maleate.Thealkyl ester will then be united with the resin by polymerization.This could not be accomplished with the saturated type of alkyd, e. g.,phthalic acid esters of polyhydric alcohols.

Resins which contain a plurality of alpha, beta enal groups aresensitive to light, heat and polymerizing catalysts. Since oxygen tendsto cause these resins to polymerize, it is desirable that the resinsshould be made in the absence of this substance,' especially whencolorless resins are required. The exclusion of oxygen and polymerizingcatalysts is desirable during the preparation of the resin and thepresence of dissolved oxygen in the original reactants is alsopreferablyavoided. Moreover, dust and extraneous particles that reagentsmay pick up usually should be removed, especially if colorless resinsare.desired. One manner in which the dissolved gases and otherextraneous impurities may be removed is through the distillation of theingredients into the reaction chamber in theabsence of air.

In order to keep oxygen from contact with the reactants, an inert gassuch as carbon dioxide or nitrogen may be introduced into the reactionchamber. This may be done either by merely passing the gas over thesurface or by bubbling the gas through the liquid reactants. In thelatter instance it may be made to perform the added function ofagitating the mixture, thus eliminating the necessity for mechanicalagitation. The inert gas will also carry away at least part of the waterformed, and toward the end of the reaction it can be used to carry awaythe reactants still remaining unreacted. Upon sep-.

aration of the water vapor the used carbon dioxide or other inert gaswould be particularly suitable for making high grade colorless resinssince any residual reactive impurities such as oxygen would have beenremoved in its passage through the first batch of-resin reactants.

The effect of light is not so important if the reactants are purifiedand the reaction carried on in aninert atmosphere, as outlined above.However, as an added precaution the esterification may be conducted inthe dark. It is also advisable to' avoid local overheating, anddiscoloration is minimized if' the reaction is conducted below atemperature of about 200 C. To avoid overheating it is advisable toraise the temperature slowly at the beginning, especially if ananhydride be used since the reaction between an anhydride and an alcoholis exothermic.

The preparation of the reactive resins is illustrated in the followingexamples, the reactants being given in parts by weight.

Preparation of resin ".A

manner. For example, the following reactive resins may be modified withtetrahydroabietyl alcohol: ethylene glycol fumara'te, diethylene glycolfumarate, alpha propylene glycol maleate, polyethyleneglycol maleates,(e. g. hexaethylene glycol maleate) polymethylene glycol maleates (e.'g. decaniethylene glycol maleate), octadecandiol fumarate, the maleicesters of 2,2-di-. methyl propanediol-1,3, glycerol maleateundecylenate, triethylene, triethylene glycol chlormaleate, triethyleneglycol terpene maleate (derived from the interaction of mol of terpeneand 1 mol of maleic in the presence of an excess'of terpene).

Many different modified alkyd resins maybe employed in conjunction with.the hydroabietyl alcohol modified resins. Such modified resins includeall of those previously mentioned and generically described as modifiedwith a mono-' hydric alcohol or with a monocarboxylic acid or with botha monohydric alcohol and a monocarboxylic acid. Amon the alcohols whichmay be used are n-butanol, 1,2 and 1,3-dichloropropanols(HOCH2-CHCl-CH2C1 and.

CHzC1CHOCH2Cl) the amyl alcohols, cyclohexanol,,n-hexancl, 2- methylhexanol, n-octanol, decanol, dodecanol, tetradecanol, cetyl alcohol.octadecanol, reduced geraniol, reduced fatty oils such as coconut oil,palm oil, etc., benzyl alcohol, phenylethyl alcohol, furfuryl alcohol,tetrahydrofurfuryl alcohol, and variousether alcohols such asCHzC1CHOHCHz-Ophenyl phenylOCHz-CHOH CH2 0 phenyl,

the monobutyl ether of ethylene glycol, the

. I Parts Fumaric acid (5.5'mols) 638 Diethylene glycol (5 mols) 530Tetrahydroabietyl alcohol (1 mol) 1 292 Fumaric acid and diethyleneglycol are charged into a resin kettle together with 146 parts ofalcohol. The resulting mixture is heated for about 4 hours at 180 C.,after which the remainder of the alcohol is added and the reactingmixture is heated to about 200 C. and maintained at that point for about1.5 hours. During the reaction about 175 parts of water are freed anddistilled oil, and the resin obtained has an acid number of about 49.

Preparation of resin "B" Parts Diethylene glycol 106 Fumaric acid 116Linseed oil fatty acids '23 These substances are heated to about 180. Cfor about 8 hours under an atmosphere of carbon dioxide to obtain aresin, having an acid number of about 42.

The resins prepared in the manner illustrat--" ed above are merelyexemplary of the reactive resins which I contemplate using for reactionwith a material containing the CH2=C group in the practice of myinvention. Other resins of the same type may be prepared in a similarmonobutyl ether of diethylene glycol etc. Fur thermore, variousmonohydric alcohols may be reacted with glycidol and the reactionproducts thereof employed as a glycol in the preparation of theunsaturated alkyd resins. Of the cycloaliphatic alcohols, those derivedby reaction of dienes with unsaturated aldehydes followed by reductionsuch as isohexyl cyclohexyl carbinol which is obtained by reducing thereaction prod uct of beta myrcene with acrolein, are especiallysuitable. Various acids and other compounds having esterifiable hydroxylroups may be employed in the modification of the unsaturated alkydresins to be used in accordance with my invention for copolymerizationwith allyl compounds. Thus, for example, the hydroxy acids may beemployed, including lactic acid, alphahydroxyisobutyric acid,hydracrylic acid, omegahydroxycaproic acid, omega-hydroxydecanoic acid,omega-hydroxymyristic acid, etc. Other substances containing hydroxylgroups which may be used are, for example, ethylene cyanohydrin. Stillother alcohols which may be employed are terpineol, fanchyl alcohol, andthe unsaturated alcohols including allyl alcohol, meth allyl alcohol,oleyl alcohol, linoleyl alcohol. I have found that copolymers of alkydresins modified, with monohydric alcohol give especially hightemperature resistance when employed as a bond to laminate glass clothor when glass fibers are used as a filler in castings or moldings. 1

, Itis preferable that primary alcohols be used as modifiers. for theunsaturated alkyd resins, and it is also preferable that alcohols haveboiling points above about 200 C. If low boiling al- Accordingly, theesterification is conducted in an organic solvent which dissolves thereactants as well as the resultant resin and which is preferablysubstantially insoluble in water. Examples of these are: benzene,toluene. xylene, chloroform, carbon tetrachloride, ethylene dichloride,propylene dichloride, ethylene and propylene trichlorides, butylenedichloride and trichloride and also higher boiling solvents such ascresol and methyl cyclohexanone although some of these may tend todarken the resin. The mixture is refluxed in such a manner as toseperate the water formed by the estorification. Much lower temperaturesare used than are used under the conditions outlined in the examples.Suitable temperatures range between 90-145 C., for example, for theboiling members of the group of solvents set forth above. Obviously,-this will vary with different solvents and with difi'erentconcentrations of solvent. The range of preferred concentrations for theinert solvent is from about 25% to about 50%. An esterification catalystis usually necessary because a comparatively low temperature isemployed. Examples of these are thymol sulfonic acid, d-camphor sulfonicacid, napthalene sulfonic acid and ptoluene sulfonic acid. Obviouslyother known esterification catalysts could be used. A resin having anyparticular acid number, if made azeotropically, will usually have alower viscosity than one of the corresponding acid number not madeazeotropically.

Monocarboxylic acids which are saturated may be employed as modifiersfor the unsaturated monocarboxylic acids heretofore mentioned. Suchacids include acetic acid, caproic acid, lauric acid, stearic acid, etc.Any of the monocarboxylic acids which are available in the form of theanhydride may be used as the anhydride instead of as the acid.

When a resin is treated with a reactive material containing the CH2=Cgroup, the material may or may not dissolve the resin, depending on thechemical nature of both the material and U the resin. If the resin beincompatible with this reactive material, chemical interaction of thetype described cannot occur. Under these conditions another solvent maythen be introduced as an additional constituent. If the solvent isinert, it plays no part in thereaction but is so selected that both thereactive material and the resin are soluble yielding a homogeneoussystem of reactive material, inert solvent and resin. This inventionrelates to compatible combinations of. a reactive resin and a reactivematerial containing the CH2=C group. Such combinations may be obtainedby the use of inert blending solvents where necessary althoughthe use ofonly reactive materials containing the CH2=C group which act as solventsis preferred.

The terms compatible and homogeneous as used in the specification andclaims are intended to indicate a system, the constituents of which areuniformly distributed throughout the whole mass, and when applied tosolutions, to indicate that they may be either true solutions orcolloidal solutions as long as they are substantially stable.

when a reactive resin and a reactive material containing the CH2=C groupundergo chemical reaction, certain possibilities arise. The reactiveresin and reactive material may combine in such a manner as to lead tothe formation of a resinous colloidal entity, and the end-product isclear, glass-like and homogeneous. Alternatively,

the reactive resin and the reactive material may interact in such amanner as to yield colloidal entities wh'erein varying degrees ofopacity or colloidal colors result. The end-product under theseconditions may be partially translucent or opaque.

The final resin composition is obtained by dissolving a resin containingthe alpha, beta enal (Causa groups in a reactive material containing thegroup C=CH:. The chemical reaction which is believed to take place is acombination of the reactive material with the resin at the points ofunsaturation, yielding a less unsaturated system which is essentiallyinsoluble and infusible. Ordinarily when a resin is dissolved in asolventfthe changes which occur are physical in nature. The resin may beisolated from the solvent mixture chemically unchanged. In the presentinvention, however, the combination of the reactive material containingthe CH2=C group which acts as the solvent and the reactive resin becomean inseparable entity, the original ingredients not being capable ofbeing removed by solvents for the original ingredients.

Through the use of a small amount of reactive alkyd resin dissolved in alarge amount of reactive material containing the CH2=C group, the finalcomposition contains not only the ester groupings which were originallypresent in the alkyd resin but also the carbon-to-carbon molecular bondswhich link the reactive material and the reactive resin. Through the useof a small amount of resin and a large amount of reactive material, thecomposite resin is no longer soluble in those inert solvents whereinthe'reactive material resinified alone would dissolve. Under longexposure to the inert solvent the composite resin v will tend to imbibea certain quantity of inert solvent, but it does not possess thesolubility of the reactive material when resinified alone. This propertyis a distinct advantage in that the physical contour of an object madeof resin is not lost through solution.

Comparison of the softening point of the reactive material containingthe CH2=C group alone and of the softening point of the composite resinformed through interaction of the resin and reactive material shows thatthe softening point of the latter has been raised. The softening pointmay be increased very markedly depending upon the ratio of resin used inthe composition.

In general the softening point of resins has a distinct bearing on theirbehavior at room temperature as well as at elevated temperatures. Wherethe softening point is too low, difiiculty is encountered in thatarticles made from the resin slowly lose their shape. In largearticles,the eifect becomes very noticeable. A softening point when too high, onthe other hand, results in a composition which Will not softensufiiciently in a mold. Roughly, three types of compositions exist withrespect to the ratio of resin to reactive material containing the CH2=Cgroup. ,First, a large amount of reactive material and a small amount ofresin; second, substantial quantities the polymerized under'he at andpressure. l

1sof both ingredients; third, a large amount of resin and a small amountof reactive material.

quantities of both reactive material containing" the CH2=C group andreactive resin in the cured state may be machined, turned on a lathe,sanded and polished and used in general as a turnery composition. Theabsence of softening renders the material particularly adaptable to thispurpose. In that it is unflowable, it may be machined without danger ofsoftening and gumming tools. Moreover, such a composition may, ifdesired, be obtained in large blocks.

My resins may be utilized in: moldings, with or without filler;laminated materials as the bonding agent; adhesives; coatingcompositions for use in finishes for wood, metals'or plastics, or in thetreatment of fibrous materials such as paper, cloth or leather; asimpregnating agents for fibrous materials; as assistants in dyeing, etc.

In order to use the composition for moldings, it may be necessary toprevent the composition from curing too fast. During the change from aliquid'to a hard resin, varying stages of hardness exist and byinterrupting the reaction at a definite point,'the material may then beplaced in a form and hardened under heat. Sheets of resin may be twistedormade to conform to a pattern and then subsequently cured in the shapedform by heat alone I One manner in which this may be accomplished is topolymerize the reactive resin and reactive material containing theCH-.-=C' group without catalysts until the material is no longer fluidbut still not, completely cured. By grinding this partially polymerizedmaterial a molding composition is obtained which can then be shaped Toproduce moldings or laminated materials, combinations of reactive resinand reactive material containing the CH2=C group may be mixed with oneor more of the various fillers, e. g. wood flour, wood fiber, paper dut, clay, diatomaceous earths, zein, glass wool, mica, granite dust, silkflock, cotton flock, steel wool, silicon carbide, paper, cloth of anyfiber including glass, sand, silica fiour, white, black or coloredpigments, etc. Such mixtures may be partially polymerized, ground andmolded. On the other hand, the liquid composition may be bodied andintroduced directly into a mold and polymerization from a viscous liquidto a solid resin conducted in one step.

In that the composition of reactive resin and reactive material isinitially quite limpid, it may be used for impregnating various porousobjects or it may be employed as a coating composition.

If the polymerizable compositions are to be molded under low pressure e.g. -50 pounds/sq. in), the composition may be employed without bodyingor' partial polymerization.

The liquid polymerizable mi ture may be introduced in a positive moldwithout any filler. In this instance, however, the reaction becomesquite exothermic but this may be conveniently controlledby the additionof a suitable polymerization inhibitor.

The ratio of reactive material containing the CH2=C group to reactiveresin in the final composition will not only have a bearing. on theaasaaoc softening point and on methods of working the resin, but onvarious other physical properties, e. g. light transmission, scratchresistance, indentation hardness and arc resistance.

' induce heat in the reactive mixture to polymerize the latter.

During the transformation of the soft, limpid resinous composition to ahard massive structure, various stages occur which may be roughlyseparated as follows: first, the induction period wherein the materialremains as a sol which slowly increases in viscosity; secondly, thetransformation of the sol into a gel; and third, the hardening of thegel.'. During the transformation of the sol to a gel, an exothermicreaction occurs which may be very violent if .uncontrolled. Moreover,the gel has relatively poor heat conductivity resulting in poor transfernot only of external heat but of the heat that is generated duringchemical reaction throughout the mass. Cognizance has to be taken ofthese features in the hardening of the composition, particularly in thecasting or molding of large blocks.

Light, when used alone, causes a relatively long induction period andduring the transformation of the sol to the gel requires cooling toovercome the exothermic reactions especially when a powerful source oflight is used for final curing. Using heat alone, gelation occursreadily enough at appropriate temperatures but since the gel, whenformed, has poor heat conductivity, fracturing may occur in the laststage. Through the use of heat and catalyst, the reaction may becomevery violent unless the heating is carefully controlled.

Various combinations of these three factors may be used to bring abouthardening of the mass. Mild heating of the reactiveresin and reactivematerial containing the CH2==C group, with or without inhibitors, bringsabout a very gradual increase in viscosity which may be controlled quiteeasily and readily. When the solution has taken on an appropriateconsistency, then accelerators may be introduced and heating conductedata very much lower temperature. Mild heating may first be used and .themass then exposed to light. Use of superoxides and light is veryeffective. In other words, through the use reactive material containingthe CH=C group are originally liquid compositions and by propertreatment at relatively low'temperature they can be converted intohardmasses. The wide divergence of the properties of suchcompositionsenables them to be used in a variety of different ways. In the liquidform they may be used as an adhesive, impregnating agent, or as asurface By a judicious selection of the ratio of reactive matediversesubstances together, wood, metal, glass, rubber, or other resinouscompositions such as phenolic or urea condensation products. .As asurface composition in the liquid form, softening agents, celluloseethers or esters could be added as well as natural orartificial resins,and the 18 Many of the advantageous properties of the resin resultingfrom'the polymerization of mixtures containing reactive materialsccntaining the CH2=C group and reactive resins are apparent from theforegoing disclosure. Several important advantages are now to be setforth.

In molding and casting operations curing takes place either in thepresence or absence of air very rapidly. This is of great importance incuring large blocks. Other alkyd resins require a very much longer timeto cure in large blocks,

i. e. many months, whereas the composition of a reactive resin andreactive materials containing hardening brought about with light orthrough 9 catalysts such as cobalt salts, oxygen liberating substances,etc.

latter frequently remains tacky for a relatively lengthy period. Inorder to overcome this, drying oil fatty acids, e. g. linseed oil fattyacids, are added to the esterification mixture in making the originalreactive resin and this will cause the top surface to dry quickly uponsubsequent polymerization with a reactive material containing the CH2=Cgroup. In this way a coating composition is obtained which dries bothfrom top and bottom.

The liquid resinous composition, moreover, may be cast or molded andafter hardening may be isolated as a finished product, or it can be cut,turned and polished into the desired finishedproduct. Provided thesurface of the mold is highly polished, the resinous substance acquiresa clear, smooth finish from the mold. The compositions so obtained,being insoluble, are not easily attacked by solvents and, beinginfusible, may be worked with ordinary wood-working or metal tools. Theartificial mass can be cut, turned on a lathe, polished and sandedwithout superficial softening andstreaking.

Obviously, natural resins or other synthetic resins may be admixed withthe resins of this invention in order to obtain products suitable forparticular purposes- Examples of these are shellac, cellulose esters andethers, urea resins, phenolic resins, alkyd resins, ester gum, etc. Theresins of my invention may also be mixed with rubber or syntheticrubber-like products if desired.

Since many of these resins are originally transparent and free of color,they may be colored with suitable dyes to a wide variety of transparentsoft pastel shades. An example of a suitable dye is Sudan IV. Darkershades may be obtained ifdesired, e. g., with nigrosine.

It may be desirable in some instances to form Since these compositionsdryfwu from the bottom rather than from the top, the

the CH2=C the most.

Another important advantage is the fact that the reactive materialcontaining the CHa=C group which acts as the solvent combines with theresin leaving no residual solvent and giving no problems as to solventremoval.

One of the outstanding advantages of these resins is quick curing timewhich renders them available for injection molding, blow molding, andextrusion molding.

Similar advantages are present in coating operations such as the lack ofshrinkage of the film due to loss of solvent because of the combinationa copolymer of one or more substances containing the group CH2=C and atleast one polymerizable unsaturated alkyd resin and, after molding orcasting this into any desired shape, to apply a coating of a hardercopolymer to the outside, thus obtaining the same effect as is obtainedin the metallurgical fields by case hardening. Similarly, inserts may befilled with a hard resin in order to act as bearing surfaces or for someother purpose. Such coatings or inserts adhere tenaciously and appear tobecome integral with the original piece. In order to secure the bestresults in manufacturing such products, it is desirable to first abradethe surface of the article before the application of the harder film.Duringthe curing operation, the abrasion marks disappear. This treatmentis also of considerbetween the reactive resin and the reactive materialcontaining the CH2=C group which acts as the solvent. Furthermore, thecomposition dries from the bottom, there are no bubbles from thesolvent, and there is no water driven off. A clear, bubble-free,impervious coating is therefore more readily obtainable with thecombinations of a reactive resin and reactive material containing theCH2=C group than with other coating compositions, Sincethere is nosolvent to be removed and since air is not needed to dry thecompositions, relatively thick applied in one'operation.

This application is a continuation-in-part of my "copendingapplications" Serial No. 555,194 filed September 21, 1944, and SerialNo. 540,142 filed June 13, 1944, now U. S. Patents Nos. 2,443,741 and2,443,740, respectively.

I claim: I I

1. A product produced by interpolymerizing a mixture including from5%-95% of a polymerizable unsaturated alkyd resin chemically modifiedwith tetrahydroabietyl alcohol and from 95%-5% of styrene.

2. A polymerizable composition comprising from 5%-95% of a polymerizableunsaturated alkyd resin chemically modified with tetrahydroabietylalcohol and from 95%-5% of styrene.

3. A polymerizable composition comprising from 5%-95% of a polymerizableunsaturated M alkyd resin chemically modified with tetrahydroableimportance since it may be used to refinish articles which might havebeen marred in use. copolymer obtained by interpolymerizing apolyabietyl alcohol, from %-5% of styrene, and a catalyst foraccelerating the copolymerization of said unsaturated alkyd resin withsaid styrene.

4. A polymerizable composition comprising (1) from 5%-95% of anunsaturated alkyd resin obtained by reaction of ingredients comprisingethylene glycol, fumaric acid and tetrahydroabietyl alcohol, and (2)from 95%-5% of styrene.

5. A molding composition comprising (1) a filler, (2) a polymerizableunsaturated alkyd resin chemically modified with tetrahydroabietylalcohol, (3) styrene, and (4) a catalyst for accelerating thecopolymerization of (2) and (3), 2) and (3) being present in saidmolding composition in a weight ratio of from 4:1 to 1:4.

6. A shaped article comprising a filler and a group require only a fewdays at layers may be merizable composition comprising an unsaturatedalkyd resin chemically modified with tetra-' hydroabietyl alcohol andstyrene, said unsaturated alkyd resin and said styrene being present insaid polymerizable composition in a weight ratio of from 4:1 to 1:4.

7. A- laminated article comprising a plurality 01 sheets of fibrousmaterial bonded together with EDWARD L. KROPA. 15

REFERENCES CITED The following references are of record in the iile oithis patent:

onrrnn s'ra'rns PATENTB Number Name 7 Date Rummelsberg Jan. 12, 1937Ellis Mar. 26, 1940 Ellis Sept. 9, 1941 D'Alelio' Oct. 21, 1941 KropaJune 22, 1948 Kropa June 22, 1948

